Refining cast-iron



H. BARNES.

REFINING CAST IRON.

APPLICATION FILED FEB. 61

1 ,322,51 6. Patented Nov. 25, 1919.

z ,6 f 9 J 2/ 4 ("Y i Z .l i g I"? 7 4 7 furnace of approved construction.

bustion.

HERBERT BARNES, 015' CHATTANOOGA, TENNESSEE, ASSIGNOR OF ONE-HALF T0 ROBERT H. GENTER, 0F CHATTANOOGA, TENNESSEE.

REFINING CAST-IRON.

Specification of Letters Patent.

Patented Nov. 25, 1919.

Application filed February 6, 1919. Serial No. 275,411.

To allwhom it may concern:-

Be it known that I, HERBERT BARNES, a citizen of the United States, residing at Chattanooga, in the county of Hamilton and State of Tennessee, have invented certain new and useful Improvements in Refining Cast-Iron, of which the following is a specification.

This invention relates to refining cast iron by removing more or less of the carbon and other impurities from it while it is in a molten condition; and it consists of the method of procedure and of a furnace constructed and operated as hereinafter fully described and claimed.

In the drawings, Figure l is a longitudinal section through a furnace constructed according to this invention. Fig. 2 is a plan view of the same. Fig. 3 is an end view of the fire-box. Fig. 4 is a cross-section, taken on the line 4-4 in Fig. 2 and showing the pipe for introducing air into the molten metal.

The furnace is provided with a refining chamber or collecting chamber having a hearth 2, similar to that of a reverberatory A firebox or gas producer 3 is provided at the front end of the hearth, and has a grate 4 for supporting the fuel which forms the principal supply of gas for the furnace. A melting chamber 5 for the cast iron is provided at the rear end of the hearth 2. This chamber 5 has a curved and tapering bottom portion 6 for the molten metal to flow down by gravity onto the hearth. A charging door 7 ,is provided at one side of the upper part df the chamber 5, and 8 is a lateral passage which connects the upper part of the chamber 5 with a stack or chimney 9 for carrying off the products of com- Blast pipes or twyers 10 for air are arranged to project into the tapering bottom portion 6 of the melting chamber. These twyers 10 project through the top wall of the furnace and are arranged in a downwardly and rearwardly inclined position. These twyers have internal jet pipes 12 arranged concentric with them, and adapted to supply oil or other similar fuel to the lower part of the melting chamber. The

molten metal 14 is indicated by dotted lines in Fig, 1, and 15 are the outlets through which it is tapped off when sufficiently refined. The bottom of the hearth is suitably curved or inclined, and these outlets are placed at its lowest part.

Blast pipes 16, for introducin air below the surface of the molten meta, are provided, and are arranged in an inclined position and are connected to. a blast pipe 17.

.A second series of blast pipes or twyers 18, similar to the blastpipes 10, is provided at the other end of the hearth from the melt ing chamber and adjacent to the fire-box 3. These blast. pipes 18 are arranged in a downwardly and rearwardly inclined posi-v tion, and they project through the top wall of the furnace.

The various blast pipes are all connected by means of the trunk pipe 30 to a blower or air pump of approved construction, and are provided With'suitable regulating valves at all necessary points. A stop valve 20 is provided for cutting off the blast from the rear twyers 10, and a stop valve 21 is provided for cutting ofl the blast from the front twyers 18. A branch blast pipe 24: is provided, and is arranged to deliver air under the grate of the fire-box so as to support combustion and aid in the production of combustible gas.

When the furnace is started, a fire is built and maintained on the grate so as to form a large supply of combustible gas which is ignited and which heats the hearth and the middle part of. the furnace, but whichis not, permitted to burn freely on the hearth. The pig iron isplaced in the melting chamber, and the air blast is turned on through the twyers 10, the twyers 18 being closed. The blast of air mixing with the gas from the fire-box induces an intense heat in the lower part of the melting chamber, and this heat can be increased, if desired, by introducing oil or other similar fuel through the jet pipes 12. When the metal melts it flows down onto the hearth, and when a suflicient body twyers 10 and is turned on through the twyers 18. This produces an intense heat over the hearth, and the waste heat passing to the stack keeps the melting chamber at a "relatively high temperature. The molten of molten metal has accumulated on a the hearth, the blast is shut off from the placed in the melting chamber and heated by the waste heat.

- The blast is changed and varied between all the twyers or blast pipes by means of the suitable valves provided for that purpose,

so as to produce the best efiect, and as found desirable by actual experience.

What I claim is:

1. In a furnace for refining cast iron, a refining chamber provided with a hearth for the molten metal, a gas producer at the front end of the said hearth, a melting chamberfor the pig iron having a curved and tapering bottom portion connected directly to the rear end of the refining cham:

ber above the said hearth, rear blast pipes projecting downwardly and rearwardly into the curved and taperingbottom portion of the melting chamber, and front blast pipes projecting downwardly and rearwardly into the front end portion of the refining chamber above the hearth and to the rear of the outlet from the gas producer to the refining chamber.

2. In a furnace for refining cast iron, a refining chamber provided with a hearth for y the molten metal, a gas producer at the front end of the said hearth, a melting chamber for the pig iron having a curved and tapering bottom portion connecteddirectly to the rear end .of the refining chamber above the front blast pipes projecting downwardlyand rearwardly into the front end portion of the refining chamber above the hearth and to the rear of the outlet from the gas producer to the refining chamber.

3. In a furnace for refining cast iron, a refining chamber provided with a hearth for the molten metal, a gas producer at the front end of the said hearth, a melting chamber. for the pig iron having a curved and tapering bottom portion connected directly to the rear end of'the refining chamber above the said hearth, rear blast pipes projecting downwardly and rearwardly into the curved and tapering bottom ortion of the melting chamber, blast pipes or introducing air be low the surface of the molten metal arranged at the middle part of the refining chamber, and front blast pipes projecting downwardly and rearwardly into the front end portion of the vrefining chamber above the hearth and to the rear of the outlet from the gas producer to the refining chamber.

In testimony whereof I have afiixed my signature.

HERBERT BARNES. 

